Expensive air filters!!!ho...........

How often should i change these 4" 21x 23 or close..filters .they are pricey to say the least [$24.00] around here, my wife thinks every 6 monnths?Shes usually wrong,on this stuff. so asking you here?I blow them out with my compressor fairly regular....they don't eveer have much dust in them. Have you a better idea i am listening intently thanks much for reading this thread bob s

Advertisement

blowing them out is not a good idea. same as blowing out the expensive air filter for your car engine. my method is to hold them up to a light bulb. if you can see thru it reasonably well then keep using it. there is no scientific method to tell anyone when to changer a filter as everyones house and amount of dirt is different. once a month for some people and once every six months for others. depends on the house/pets etc. if you take a high end filter and brush or blow it out it can make tiny holes and a merv 16 filter will become a merv 10 from the tiny holes you created. we are talking micron sized holes, not something you can see but those filters when undamaged can take out micron size particles if that is important 2 U. money is more important to others so to get it to work to its rating just use it until it looks dirty IMO.

do you own a BSA motorcycle? those were cool along with the old Triumphs.

You'll get a lot of opinions here about that.
It depends on how much particulate is generated or created in your home.
(the drier the enviorment the more thats created, carpets, drapes etc. as well as pet, kid activity.)
What level of dust screening you are looking for. (medical sensitivities to dust..Lung conditions)
The measured temp rise on your furnace. (Get a thermometer and learn how to test your furnace's temp rise to make sure that your filter decisions are not hurting your furnace.

And Yuri
how did a BSA get into this thread?
BSA lightning was my first followed by a Triumph tiger.

blowing them out is not a good idea. same as blowing out the expensive air filter for your car engine. my method is to hold them up to a light bulb. if you can see thru it reasonably well then keep using it. there is no scientific method to tell anyone when to changer a filter as everyones house and amount of dirt is different. once a month for some people and once every six months for others. depends on the house/pets etc. if you take a high end filter and brush or blow it out it can make tiny holes and a merv 16 filter will become a merv 10 from the tiny holes you created. we are talking micron sized holes, not something you can see but those filters when undamaged can take out micron size particles if that is important 2 U. money is more important to others so to get it to work to its rating just use it until it looks dirty IMO.

do you own a BSA motorcycle? those were cool along with the old Triumphs.

thanks All i restored some of these britbikes. i Have several street rods and kustoms and cushmans.I sold the bsa to fellow who came from brittan and piicked it up at my shop in michgan
about two years before i restored a70 bonneville.which i sold to a jeweler in bangkok. i really liked riding these bikes...so after i tore up my right foot and knee . i bought a 2004 basket case america w/electric start .That is great bike no matter what anyone says. So i still have that bike............I am lookin forward to spring now and I have A 2003 shadow which rides great too.

You'll get a lot of opinions here about that.
It depends on how much particulate is generated or created in your home.
(the drier the enviorment the more thats created, carpets, drapes etc. as well as pet, kid activity.)
What level of dust screening you are looking for. (medical sensitivities to dust..Lung conditions)
The measured temp rise on your furnace. (Get a thermometer and learn how to test your furnace's temp rise to make sure that your filter decisions are not hurting your furnace.

And Yuri
how did a BSA get into this thread?
BSA lightning was my first followed by a Triumph tiger.

OK, his handle..I see it now.

this was al installed by heating contrctor 18 years ago Would a heating contractor know how to do this furnace temp test. it seems like they knew what they were doing when installation was done, i will quit blowing out the filter though, i am Damaging it with 100 psi . wow i didn't realize this. bob s

A Temp rise test is just punching a small hole 5' downstream in your hot air plenum to put a thermometer in. (Out of a direct sight line of the exchanger). You might already have that hole there that's probably covered with tape. Turn up the heat for 10 minutes and then record the temp reading. Subtracting the return air temp(use the current house temp..70F) from the hot air plenum measurement will give you the temp rise.
The recommended temp rise range will be written on the info plate inside the furnace. Your calculated temp rise measurement should fall within the listed temp range.

My unit doesn't have all that fancy stuff so I check my filters with a home made water manometer. If I get a half inch WC more than when the filters were new I replace them. I have no idea whether right or wrong according to manufacturing specs but it has ran longer than I can count fingers and toes and that's kinda higher math for me.

My unit doesn't have all that fancy stuff so I check my filters with a home made water manometer. If I get a half inch WC more than when the filters were new I replace them. I have no idea whether right or wrong according to manufacturing specs but it has ran longer than I can count fingers and toes and that's kinda higher math for me.

My unit doesn't have all that fancy stuff so I check my filters with a home made water manometer. If I get a half inch WC more than when the filters were new I replace them. I have no idea whether right or wrong according to manufacturing specs but it has ran longer than I can count fingers and toes and that's kinda higher math for me.

checking static pressure is the best way to see if the filters are

a) flow restrictive from the start (write the reading down no filter and filter compare!!!)
b) dirty.. compare to new (and yes .5 should work as an idicator, but others will chime in on the trades overall view of what dirty is!!)